Raptor E720 Build Thread

[Surinder Singh]

I'm thinking more about electronics.

What Kv motor would you guys recommend with the stock pinion for getting good flight times?

I'm not going to be doing smack 3d with this machine. Just slow 3d. Inverted circuits and just getting into tick tocks. I'd like to go with a motor from the Align 700mx range, but confused about Kv ratings and final head speeds. I really would like to run at a sensible head speed. This is my first 90 size machine and I'm worried that it may be a bit intimidating. So I'd like to go a little slower on the head speed to start off with.

[Stuart]

If you have excel I use this that I made.

Very simply put you need to work out what max headspeed you want.

so Volts x KV = Motors Max RPM into gear ratio = Headspeed

So my 530kv motor should reach a max of 2300 aprox

[Surinder Singh]

Thanks again Staurt.

Wondering if 1900 is do able or will I compromise tail authority by running that low?

[Stuart]

You will be fine

[Surinder Singh]

Servos HV setup or not ?

What are the advantages of going HV?

[Stuart]

personally i would say HV is a personal choice thing. It for me doesn't have massive enough advantages to warrant the spend. It generally offers greater torque but not always speed, yes you can loose a need for a bec but i just use a life battery so no need for a bec anyway.

Each to there own really.

[Stuart]

Another element is that in any design there needs to be a week point from experience so far in the G4 this is the drive train gears in the tail boom support unit the flat pinion gear fails in a bump and in the head you will pop a link and the alloy arms on the blade grips will bend.

So if have more torque in the servos then more likely this will result in more alloy bending or other links popping off.

Never yet bent a main mast or feathering shaft.... snapped off two booms and found that tail mounting the tail servo is a better option. Ironically so does TT now as the new 820e has a boom mounted tail servo

[Surinder Singh]

This is excellent info Stuart.

It's great to hear how the G4 handles a bump. I've heard from other owners about how robust this Heli actually is.
That was one of the deciding factors for me to go down the G4 route.

Could you pls, when you get time post a picture and info on how to best mount the tail servo on the boom?

Also would you say that this head design is better on the servos in a bump?
I hear that the DFC type heads can be a bit more brutal on servos in a crash situation.
How have your servos faired in crashes on your G4?

[tonystevens]

Another element is that in any design there needs to be a week point from experience so far in the G4 this is the drive train gears in the tail boom support unit the flat pinion gear fails in a bump and in the head you will pop a link and the alloy arms on the blade grips will bend.

So if have more torque in the servos then more likely this will result in more alloy bending or other links popping off.

Never yet bent a main mast or feathering shaft.... snapped off two booms and found that tail mounting the tail servo is a better option. Ironically so does TT now as the new 820e has a boom mounted tail servo

Funny you should say that, my voltage reg decided to give up the ghost today and my G4 went in on its third flight lol, only thing i broke were the fan shroud and skids! And it went in hard on its side. Pretty damn strong heli i reckon although im not sure my servos would have survived if i hadnt removed the metal tt horns

[Stuart]

Hi the head is fine for the G4 the cost of replacing a small piece alloy versus stripping a servo and time. I've attached a pic of the book mount it use the tail boom mount from quick UK and simply dremel the TT link down to fit....

[Surinder Singh]

Sorry to hear about your crash Tony.

I'm still amazed how many G4 owners are reporting on the robustness of this machine.

[Surinder Singh]

Thanks Stuart that picture helps.

I'll check out the quick uk mount.

[Stuart]

Sorry to hear you had a bump Tony i hope it was going well up to this point im considering dropping my elyq reg and putting a life also on my nitro same as my e720 then i can go sbus on the rx.

Yeh has to be the bullet proof heli ive have had in a long time. It just puts a smile on my face every time iI fly so predictable and fun.

[tonystevens]

Sorry to hear you had a bump Tony i hope it was going well up to this point im considering dropping my elyq reg and putting a life also on my nitro same as my e720 then i can go sbus on the rx.

Yeh has to be the bullet proof heli ive have had in a long time. It just puts a smile on my face every time iI fly so predictable and fun.

Was going very well stuart, felt right at home with it pretty much straight away!

[Stuart]

every time I've bumped mine its gone back together so easy isn't difficult given the low parts counts but more importantly to me it flys just like it did when new. unlike some others I've had once bumped they never felt like it did when first built.